STC is a Manufacturer of Disc Type Gear Shaper Cuttersdesigned to cut any type of gear internal or external, spur or helical.They can also be used to cut splines, serrations, sprockets, or many otherinvolute forms. These cutters are manufactured with diameters from 10mm to120mm or 0.5″ up to 4″. These are used for cutting internal gears,splines, and serrations, both spur and helical. But they may also be designedfor externals if required.